


Tentacles

by Secretly_a_wuss



Series: Monster Mash [3]
Category: Kuroshitsuji | Black Butler
Genre: Anal Sex, Canon Setting, Established Relationship, M/M, Orgasm Denial, Plot What Plot/Porn Without Plot, SebaCiel - Freeform, Smut, Sounding, Tentacle Sex, Tentacles, Teratophilia, demon!Sebastian, guys I'm sorry but I'm trash for monsters, monster fucking
Language: English
Status: Completed
Published: 2018-11-26
Updated: 2018-11-26
Packaged: 2019-08-28 03:10:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,079
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16715488
Author URL: https://archiveofourown.org/users/Secretly_a_wuss/pseuds/Secretly_a_wuss
Summary: Sebastian interrupts Ciel's relaxing bath...(This series can be read out of order)





	Tentacles

**Author's Note:**

> Hope you guys enjoy! The support on this series has been amazing! (but also I'm kinda self conscious about this one, don't know if it's too weird??)

“Master, I know you like it when I mark you, but we can't allow people to see. These ones are far too high up your collar, and the servants already suspect something going on from our noises in the bedroom” Sebastian explained as he gently touched the tapestry of bruises running up Ciel's chest. He was undressing his Lord for a relaxing bath, the demon loved to massage Ciel's skin and maintain the boy's cleanliness and purity with gentle lavender soaps. Taking care of his Lord made him feel happy, he loved to wash the boy's hair and touch his clean skin. 

The Earl sighed, allowing his butler to unbuckle his belt and pull down his shorts, the long gartered socks slipping down next. 

“But I forget in the heat of the moment, how could I possibly think of anything reasonable when you're doing such vile things to me” his Lord smirked, enjoying the subtle blush running across the demon's cheeks. There was something scandalous about taking Ciel in such monstrous forms, and for the first time in millennia, the demon was actually blushing. Perhaps the stigma and propriety of this century was rubbing off on him. His Lord was so demanding too, so uncaring of the peculiar inhuman shapes and faces he wore, Sebastian felt as though he could be his true self around the Earl and it was an entirely new experience. New experiences were rare for the demon. 

The demon kissed his master's abdomen lovingly, worshipping every inch of skin as he kneeled before his heaven. 

“Sebastian, the water is getting cold” Ciel interrupted his wondering mouth, and he sighed against the baby soft skin, long black eyelashes downcast sadly as he pulled away from the boy. 

“Of course, my Lord” the butler straightened himself and assisted his master into entering the tub. The demon settled into the pleasant task of washing the Earl's hair and scrubbing his skin, careful not to aggravate healing bite or claw marks. Sebastian felt desire run like fire on dry leaves through his veins. He ached to touch his master more intimately, his pants painfully tight as he restrained himself. Instead he rubbed the boy's shoulders harder, thumbs digging into the boy's back muscles to rub out any tension remaining. Ciel melted under his touch, sunk further down in the bath, legs stretching out as the butler’s hands turned his muscles into jelly. 

He grabbed one of Sebastian's ungloved hands and admired the ink coloured nails and demonic pentagram claiming the devil as his. Ciel startled his butler when he guided the captured hand under the water and onto his stiff length. The Earl sighed in pleasure as the demon quickly understood his desires and responded by giving him a firm stroke. 

“I simply wanted to be clean before we did anything” the Earl reasoned, eyes closed as he rocked up into the butler's tight grip. 

“Let me join you” Sebastian begged voice growing deeper and more gravely. His eyes shone brighter, pupils thin slits as he jerked off his master. He could smell it in the air, his little Lord's desire, potent and heady despite the lavender scented soap that had been used to bathe him. The Earl nodded enthusiastically, his rocking hips making the water stir and lap at the sides of the porcelain claw footed bath. 

The hand stroking him morphed into a peculiar limb, something slimy and cold that pulled at the skin of his cock with an unnatural grip. And when he opened his eyes, it was the tentacle of a charcoal coloured octopus wrapped tightly around his length, it massaged him with its suction like puckers and teased the sensitive head of his member.

He looked over his shoulder to find a writhing mass of tentacles. His demon slivered in behind him and settled his amorphous form in the warm bathwater, the tentacles spread out, clogging the bathwater like weeds and snaking around his legs. They wiggled and pulsed against his back, wrapping around his body and teasing his skin with their duel rows of puckers. This new form had dark black flesh and a paler undercoat for its two rows of parallel feelers. He couldn't discern a head on the creature and struggled to find Sebastian's glowing red eyes in the mass of tangled limbs. 

“You're always so beautiful Sebastian” his master praised, stroking a thick tentacle that had wrapped itself around his forearm. 

“I'm a monster” the demon spoke, a single large carmine eye appearing from the depths of midnight limbs. 

“You're _my monster _” his love insisted, and Sebastian pushed a thin slick black tentacle inside of him, reaching deeply and wiggling in a wave like pattern that had his Lord panting and moaning.__

The demon didn't really fit in the small bath, _couldn't _fit all of his long tentacles inside the small porcelain tub. Instead they spread out all along the tiled floor like cracks in stone, their numbers far too many to count. Sebastian wrapped his master up, every one of the boy's limbs had hungry tentacles twisted around them, and Ciel smiled as the monster adored his delicate skin and worshipped his elegant body, whispered words of praise that bubbled beside his ear. The little Lord's torso and loins were also massaged and rubbed as the puckers sucked a few dozen hickeys across his skin, leaving blooming red pucker marks behind to claim his Lord's skin. Only his face was left uncovered so the vile creature could watch the boy's beautiful expressions.__

____

____“Sebastian!” Ciel cried as a second tentacle entered him, both of them thrusting in and out of the boy's tight entrance. Another inky black limb pushed past his rose lips and tangled with his tongue in an unusual kiss before pulling away, leaving the Earl gasping for breath. The young Lord was already close to coming and he found himself annoyed at his weak stamina. When Sebastian took him in a monstrous form he was always the first to cum, but could he really blame himself when the demon touched him like that._ _ _ _

____

____“Master” a frightening voice growled and the rough tone went straight to Ciel's aching cock. He came with a heated moan as a third cold limb breached his entrance, his release only seemed to spur the abomination on, encouraging its invasive tentacles and puckered ministrations. The limbs were naturally lubricated with some kind of silky slime and were cold to the touch, while they felt strange at first their slick exterior made them fairly painless to take. More tentacles slithered around his fingers and held onto his limbs, they anchored him as he was probed and pleasured._ _ _ _

____

Ciel Phantomhive _loved _those tentacles.__

______ _ _

______One found his prostate and latched on with a round feeler, proceeding to suck and tense unforgivingly, bringing the little Lord to the heights of ecstasy. He was instantly hard again and he moaned deeply at the intensity, not even noticing a fourth slip into his hole. Sebastian's tentacles spasmed and writhed inside of him pushing in and out in torturous waves while the puckers pulled at his walls with every pulse._ _ _ _ _ _

______ _ _

______It was strange to be taken by something without a proper body, it was just a collection of winding tentacles and their tight puckers, a single eye to watch him moan and the sound of splashing water as the creature explored his insides. Perhaps he'd request tentacles again later, maybe with an actual body too, so he could hold onto something while being fucked like this._ _ _ _ _ _

______ _ _

______“Do you think you could take one more my love” Sebastian’s demonic voice growled and the Earl moved his legs further apart in response. He was rewarded with the demon squeezing in a fifth tentacle that had Ciel crying out wonderfully, the sound echoing loudly through the bathroom. A thin tentacle pressed against the little hole at the tip of the boy's cock, carefully sliding in as Ciel moaned and shook with pleasure. He lifted the boy's arms above his head, restricting him further as more tentacles blanketed his tiny body all trying to get a taste of his delicious delicate flesh._ _ _ _ _ _

______ _ _

______“I'm a monster” the demon growled, slowly lifting his small human out of the tub and up into the air. Arms still restrained above his head Ciel could only bask in the pleasure as he was utterly filled by cold and slick limbs. They tightened around his legs and pulled them apart further, granting the monster easy access, he was completely at the demon's vile mercy and he had never felt happier._ _ _ _ _ _

______ _ _

______“I ruin what I love” the tentacles thrust in even deeper making Ciel's eyes widen at the combined girth all stretching him open._ _ _ _ _ _

______ _ _

______“And I so very much love you” the monster hissed in his ear and the Earl's eyes rolled to the back of his head as Ciel drowned in pleasure, drool running down his chin. The Earl managed to open his eyes through the blinding ecstasy and was faced with his devil's singular crimson eye. It was large and threatening, surrounded by a mass of ebony tentacles, but was also comforting in its familiarity, merely a larger version if the eyes he'd always looked into while making love._ _ _ _ _ _

______ _ _

______He only wanted two things. Firstly, to finally be allowed release since he was being abused from every angle, but denied by the tentacle inside his cock and the ones strangling his member by wrapping tightly around it. And secondly, he wanted to kiss his love, he wanted to feel the butler's warm lips on his own._ _ _ _ _ _

______ _ _

______His demon's beautiful human face emerged from the nest of demonic appendages seemingly at his request, although he had no idea how Sebastian knew of his desire as only lustful moans had slipped past his lips. This time though Sebastian’s skin was a demonic ebony, dark as a shadow or drop of ink._ _ _ _ _ _

______ _ _

______“How did you- ah! Fuck!” Ciel was interrupted by a particularly pleasant wave of movement from the tentacles curling inside of him. Their affection was cold and slimy and he felt the beast's natural lube dribble down his thighs before it dripped into the cooling bathwater._ _ _ _ _ _

______ _ _

______Sebastian's lips crashed into his own, their mouths battling hungrily, charcoal lips pried open his own to deepen the kiss, but instead of a warm tongue Ciel met yet another cold slimy tentacle. His eyes widened in surprise as it entered his mouth, puckers playing with his small tongue before it slithered further down his throat, wiggling and making him gag as now his every hole was stuffed. Another black tentacle pushed past Sebastian's sooty lips to wriggle into Ciel’s warm mouth and climb down his throat. They slipped between soft pink lips, another and another and another, taking his mouth in time with the limbs pumping into his stuffed entrance and he was crying by the time Sebastian pulled his face away, tentacles from his own demonic mouth still invading Ciel's and linking them together as his face melted back into black writhing tentacles surrounding two crimson eyes._ _ _ _ _ _

______ _ _

______Eventually the demon decided that his Lord had been thoroughly fucked. Ciel's prick was angry and red from overstimulation, his limbs shaking from ecstasy and so Sebastian released the human's restrained member allowing him to finally violently orgasm. Tears and drool ran down his face as the tentacles stuttered to a stop, pushing into him as much as they could one last time while Ciel’s member spasmed and sprayed white liquid into the air. It hit the white tiles with a splat, his body going limp as the pressure was finally eased. One by one the tentacles carefully left him as he was gently lowered to the cold bathroom tiles and wrapped in a soft white towel. His body covered in red pucker marks, particularly on his chest, tummy and his once pristine ass cheeks._ _ _ _ _ _

______ _ _

______Ciel felt pleasantly exhausted, every inch of his body had been massaged, and being denied his orgasm at first had made it so much stronger than usual. He heard the sound of water gurgling down the drain and his butler's warm human hands lifted him up to be carried to his room since his legs were shaking so much. They looked like they would give out entirely if he was forced to take a step._ _ _ _ _ _

______ _ _

______“I love you, Ciel” Sebastian kissed his cheek happily. And the boy smiled at the little tentacle between the demon's lips that tickled his skin._ _ _ _ _ _

______ _ _

**Author's Note:**

> I love hearing from you guys!  
> And I'm open to suggestions/requests for different monsters that Seb could turn into ;)


End file.
